1. Field
The following description relates to a microspeaker, and more particularly, to a piezoelectric microspeaker.
2. Description of the Related Art
The piezoelectric effect is the reversible conversion of mechanical energy into electrical energy using a piezoelectric material. In other words, the piezoelectric effect is a phenomenon in which an electric potential difference is generated when pressure or vibration is applied to a piezoelectric material, and the piezoelectric material deforms or vibrates when an electric potential difference is applied. Piezoelectric speakers are acoustic devices that generate sounds by applying an electric field to a piezoelectric material to cause the material to deform or vibrate.
The miniaturization of electronic devices, and similar trends, has led to the need for small, thin acoustic devices. Promising research has been conducted in the area of Micro Elector Mechanical System (MEMS) acoustic devices. Piezoelectric microspeakers, which are a type of MEMS acoustic devices, can be driven at lower voltages than electrostatic microspeakers. In addition, piezoelectric microspeakers have a simpler structure than electromagnetic microspeakers and can thus be easily miniaturized. However, piezoelectric microspeakers have lower power output than conventional voice coil microspeakers, and thus have not yet been employed extensively in mobile electronic devices such as mobile terminals.